Stornophone 5000The
Storno CQM5000 was introduced in 1979 with single, 2 or 6 channel crystal
control and optional 5-tone ZVEI or CCIR selective signalling. The first
units off the production line impressed with their excellent sensitivity
and transmitter output power (Early 25W models could easily be wound up
to over 40W although this feature was 'tamed' in the later production
models). Another impressive trick at the time was that the selective calling
still worked when the input signal was reduced just below the squelch
threshold.
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Design featuresThe
CQM5000 was designed for cost effective production, moving away from the
discrete modular approach of previous models. The bottom half of the set
was the RF side consisting of a double-sided printed circuit board containing
all the receive and transmit circuitry with a solid multi-sectional screen
which fitted over the entire transmitter and oscillator area of the board.
On the top side was the interconnection board with space for any tone
modules plus the oscillators and another screen in the case of multi-channel
sets. Most notable was the lack of wiring, being totally conectorized
with the exception of two orange wires feeding the front panel loudspeaker. |
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Technical DevelopmentsThe CQM5000 saw the introduction of broadband transmitter power amplifier design which also simplified production by reducing transmitter alignment time. Improved crystal specs allowed transmitter modulation to be achieved by direct modulation of the oscillator crystal with varicap diodes. This had the side effect of reducing the number of frequency multiplication stages required, again simplifying alignment although with multi-channel sets although it meant a modulation adjustment for each channel. Despite the success of pin diode TX/RX switching introduced in recent models, the 5000 employed a straight forward relay. |
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System capabilitiesThe
CQM5000 was introduced as an off the shelf, black box design and on the
face of it, looked less versatile when it came to custom sytstem use but
there was always something within the spirit of Storno that meant it was
soon being moulded and modified to do exactly whatever the customer wanted.
Once the synthesised CQM5000S versions accompanied by ever more advanced
tone and control boards were developed, it soon became a system radio
to equal any of it's predecessors, so much so that eventually a simplified
back to basics model was re-introduced bearing the Commtak M brand. |
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CQM5000 Toneswitch IThe
Toneswitch one was driven by the requirement for mobiles with keypad selective
calling and status entry requirements. These features were starting to
be used by the newly evolving microprocessor aided dispatch systems such
as the Storno Micropad. The tone module used a diode matrix PROM to program
the tone sequence but did not have the more advanced facilities such as
automatic repeat tone insertion. |
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CQM5000SAlthough
synthesised radios had been around for a while, the number of channels
above which it became more effective to go synthesised was steadily reducing.
The crossover point came when PROM's started to be used to select the
synthesiser division ratios. The flexibility to change frequencies or
add channels just by programming spelling the beginning of the end for
crystal controlled sets. |
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CQM5000S99 Toneswitch IIThe
Toneswitch two was one of the first fully microprocessor controlled mobiles,
advertised as allowing up to 99 channels (actually you could squeeze a
hundred in if you enabled channel 00 !) and supporting a wide variety
of tone options, the TSII had a standard 4-digit display and 15 button
keypad which could be configured to support a wide variety of systems,
including CAF2004 (which suddenly sounds quite up to date again now). |
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Storno Commtak MCommtak
was originally the product name of the 5-tone based community repeater
system. The Commtak M mobile was a single channel only CQM5000 with a
simplified front panel aimed at the low cost community repeater system
user. This version could only be supplied as a no frills model. |
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CQM5000 Binary FFSKThe
next development in selective calling was the introduction of 1200 Baud
FFSK binary signalling. This spawned a range of options ranging from transmit
only Vehicle Identification systems, flexible addressing and status reporting
and onwards to early 'digital' trunked systems. |
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Century IIThe
CQM5000 series was produced during the period Storno was owned by GE and
a Stateside version of the unit was available called the Century II. |
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| Backward: Stornophone 900 |